An unrolling carriage for strip material generally comprises a pair of support plates connected by a plurality of traverse bars or rods and has two swingable arms which can be displaced toward and away from one another along the traverses by threaded spindles to allow a roll to be engaged or disengaged by the members carried by these arms. At least one of the swingable arms can be provided with a drive for the respective roll-engaging member, thereby controlling rotation of the roll for windup or delivery of the strip material.
An unwinding carriage of this type allows the arms to accommodate rolls of different width and different diameters. The roll drive must be so dimensioned that it can remain in control even in the case of heavy rolls or coils. This means that the system must have comparatively heavy drive motors, which are usually constituted as motor-generator units so that they can positively drive the roll or brake rotation thereof selectively.
In the past, the drive motor has been mounted directly on a respective swingable arm and is usually located so that it lies within the working width of the carriage. This means that within the working width, space must be reserved for the working motor and this, of course, diminishes the working width. In addition, the heavy motor must be raised and lowered with the arms.